Description: The overall goal of this research core is to develop and validate genetic markers for cancer susceptibility. By incorporating molecular genetics and cytogenetics into population studies, the investigators hope to gain insights into the complex interactions between genetic and environmental determinants of cancer. Of particular interest are the low penetrance genes that may modulate one's response to environmental exposures and contribute to the etiology of sporadic cancers. Specific aims include maintaining and expanding communication and scientific interaction among Core and other Center members, as well as non-Center members; strengthen current and promote future research activities in the area of genetic susceptibility to environmental disease; stimulate and facilitate intra- and inter-Core grant renewals and new investigators-initiated grant proposals; and serve in consultative and collaborative roles across research and facility cores to include concept development, study design, human tissue procurement and environmental data collection. Major areas of research focus in this Core encompass: 1) the assessment of phenotypic markers of DNA damage and repair as markers of susceptibility to carcinogenesis, 2) the evaluation of polymorphisms in select metabolic and DNA repair genes and DNA adducts in the etiology of lung, bladder, breast, and pancreatic cancers, and 3) the development of statistical models for cancer risk assessment by combining biomarkers and for genotype-phenotype and surrogate-tissue marker correlation. Intra-Core 4 and inter-Core collaborative studies being conducted or completed include the following: 1) a case-control study of lung cancer examining cytogenetic and molecular determinants of tobacco carcinogenesis, 2) a study of genetic and environmental determinants, including phytoestrogen intake, of prostate cancer progression, 3) a genetic epidemiologic study of gliomas in relation to family history and genetic susceptibility markers, 4) a study of microsatellite instability and the risk of bilateral breast cancer, 5) a study of genetic polymorphisms, epidemiologic risk factors and differences in breast cancer survival among different ethnic groups, 6) a study of DNA adducts, P53 mutation spectrum, oxidative DNA damage and breast cancer risk among premenopausal women, 7) a study of molecular genetics of hereditary nonpolyposis colorectal cancer, 8) a study of modifier genes that influence age-associated risk of colorectal cancer, 9) two studies evaluating environmental and genetic determinants of advanced prostate cancer, 10) studies of second malignancies after treatment for hairy cell leukemia, acute myelocytic leukemia, 11) a study of cutaneous malignant melanoma and non-melanoma skin cancer, 12) a study of linkage and linkage disequilibrium, methods for traits, 13) a study of genetic susceptibility of bladder cancer, 14) a study of mutagen sensitivity and progression in Barrett's esophagus, 15) a study of the genetic, hormonal and behavioral determinants of obesity, 16) a pilot study of breast and colorectal cancers among Egyptians and organochlorine pesticides exposures, and 17) a pilot study to examine associations of mutagen sensitivity, oxidative damage and DNA adducts in lung cancer. The stated long term goal of this Core is to develop a validated risk model for cancer, such as lung cancer, to take into account simultaneously the effects of numerous genetic and environmental factors and the nature of subgroups (women, never-smokers, young subjects, ethnic minorities, etc). Future plans include the use of funds from the Tobacco Settlement for the State of Texas to establish an archival laboratory for the long-term storage and tracking of biological specimens and a centralized genotyping core. It also plans to expand in the area of nutritional epidemiology, and in its molecular epidemiologic studies to include brain and lymphoid malignancies. Future plans also include the development of a genotyping chip, in collaboration with Genometrix, expansion of the CRED website and implementation of multivariate statistical analysis to the large database that will be generated by incorporating chip technologies into studies.